1. Field of the Invention
This invention relates to a magnetic tape cassette having an improved impact strength and to a method of manufacturing the same.
2. Description of the Prior Art
As is well known, a magnetic tape cassette comprises a cassette body and a pair of reels which are housed for rotation in the cassette body and around which a magnetic tape is wound. The cassette body is usually formed by injection molding of plastic or the like, and a paper or the like bearing thereon a predetermined design is applied to the molded cassette body, or a predetermined design is directly printed on the molded cassette body.
The cassette body can be provided with a predetermined design by injection-molding the cassette body with a transfer film bearing thereon the predetermined design being inserted into the cavity of the injection mold. That is, the transfer film generally comprises a base film, and a releasant layer, an ink layer representing the predetermined design and an adhesive layer laminated on the base film in this order, and when molten resin is injected into the cavity with the transfer film being in the cavity, the transfer film is welded to the molded cassette body. When the base film is peeled after the molded cassette body is removed from the cavity, the ink layer is transferred to the surface of the molded cassette body. This method is advantageous over the methods described above in that the cassette body can be provided with a design simultaneously with the injection-molding of the cassette body.
However, irrespective of how a design is provided on the cassette body, an injection-molded cassette body has poor impact strength and is easily broken by a fall onto the floor or the like. This is especially so when the cassette body is formed of polystyrene resins in order to improve heat resistance of the cassette body for use outdoors.